It took me a few minutes to figure them out, so I might as well save that few
minutes for everyone else. Also, the volunteers don't seem to know how they
work.
There are two square patches that look like plain boring metal on the top of
the AC. If you push down on them, just along the edge closest to the window,
they'll flip up, and one of them has the fan speed/temp control dials
underneath it.
(this may be true of other halls too, but I've only been in South.)
hdp.